Testament is an American thrash metal band from Berkeley, California. Formed in 1983, the group originally consisted of guitarists Eric Peterson and Derrick Ramirez, bassist Greg Christian, drummer Louie Clemente and lead vocalist Steve "Zetro" Souza. The band's current lineup features Peterson, lead vocalist Chuck Billy (since 1986), lead guitarist Alex Skolnick (from 1983 to 1992, and since 2005), bassist Steve Di Giorgio (from 1998 to 2005, and since 2014) and drummer Chris Dovas (since 2023).